/* ---------------------------------------------------------------------------- */
/*                  Atmel Microcontroller Software Support                      */
/*                       SAM Software Package License                           */
/* ---------------------------------------------------------------------------- */
/* Copyright (c) 2014, Atmel Corporation                                        */
/*                                                                              */
/* All rights reserved.                                                         */
/*                                                                              */
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/* modification, are permitted provided that the following condition is met:    */
/*                                                                              */
/* - Redistributions of source code must retain the above copyright notice,     */
/* this list of conditions and the disclaimer below.                            */
/*                                                                              */
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/* this software without specific prior written permission.                     */
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/* DISCLAIMER:  THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR   */
/* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE   */
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/* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT */
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/*                                                                              */
/*                                                             modified by Keil */
/* ---------------------------------------------------------------------------- */

#include "sam.h"

/* @cond 0 */
/**INDENT-OFF**/
#ifdef __cplusplus
extern "C" {
#endif
/**INDENT-ON**/
/* @endcond */

/* External oscillator definition, to be overriden by application */
#define CHIP_FREQ_XTAL_12M (12000000UL)

#if (!defined CHIP_FREQ_XTAL)
#define CHIP_FREQ_XTAL CHIP_FREQ_XTAL_12M
#endif

/* Clock Settings (8MHz) using Internal Fast RC */
uint32_t SystemCoreClock = CHIP_FREQ_MAINCK_RC_8MHZ;

/**
 * \brief Setup the microcontroller system.
 *
 * Initialize the System and update the SystemFrequency variable.
 */
void SystemInit(void)
{

// Keil
#if (__FPU_USED == 1)
	/* enable FPU if available and used */
	SCB->CPACR |= ((3UL << 10 * 2) | /* set CP10 Full Access               */
	               (3UL << 11 * 2)); /* set CP11 Full Access               */
#endif

	WDT->WDT_MR = WDT_MR_WDDIS; /* disable Watchdog Setup             */
	                            // Keil

	/*
	 * TODO:
	 * Add code to initialize the system according to your application.
	 *
	 * For SAMG55, the internal 8MHz fast RC oscillator is the default clock
	 * selected at system reset state.
	 */

	/* Set FWS according to default clock configuration */
	EFC->EEFC_FMR = EEFC_FMR_FWS(1);
}

void SystemCoreClockUpdate(void)
{
	/* Determine clock frequency according to clock register values */
	switch (PMC->PMC_MCKR & (uint32_t)PMC_MCKR_CSS_Msk) {
	case PMC_MCKR_CSS_SLOW_CLK: /* Slow clock */
		if (SUPC->SUPC_SR & SUPC_SR_OSCSEL) {
			SystemCoreClock = CHIP_FREQ_XTAL_32K;
		} else {
			SystemCoreClock = CHIP_FREQ_SLCK_RC;
		}
		break;

	case PMC_MCKR_CSS_MAIN_CLK: /* Main clock */
		if (PMC->CKGR_MOR & CKGR_MOR_MOSCSEL) {
			SystemCoreClock = CHIP_FREQ_XTAL;
		} else {
			SystemCoreClock = CHIP_FREQ_MAINCK_RC_8MHZ;

			switch (PMC->CKGR_MOR & CKGR_MOR_MOSCRCF_Msk) {
			case CKGR_MOR_MOSCRCF_8_MHz:
				SystemCoreClock = CHIP_FREQ_MAINCK_RC_8MHZ;
				break;

			case CKGR_MOR_MOSCRCF_16_MHz:
				SystemCoreClock = CHIP_FREQ_MAINCK_RC_16MHZ;
				break;

			case CKGR_MOR_MOSCRCF_24_MHz:
				SystemCoreClock = CHIP_FREQ_MAINCK_RC_24MHZ;
				break;

			default:
				break;
			}
		}
		break;

	case PMC_MCKR_CSS_PLLA_CLK: /* PLLA clock */
		if (PMC->CKGR_MOR & CKGR_MOR_MOSCSEL) {
			SystemCoreClock = CHIP_FREQ_XTAL;
		} else {
			SystemCoreClock = CHIP_FREQ_XTAL_32K;
		}

		if ((uint32_t)(PMC->PMC_MCKR & (uint32_t)PMC_MCKR_CSS_Msk) == PMC_MCKR_CSS_PLLA_CLK) {
			SystemCoreClock *= ((((PMC->CKGR_PLLAR) & CKGR_PLLAR_MULA_Msk) >> CKGR_PLLAR_MULA_Pos) + 1U);
		}
		break;

	default:
		break;
	}

	if ((PMC->PMC_MCKR & PMC_MCKR_PRES_Msk) == PMC_MCKR_PRES_CLK_3) {
		SystemCoreClock /= 3U;
	} else {
		SystemCoreClock >>= ((PMC->PMC_MCKR & PMC_MCKR_PRES_Msk) >> PMC_MCKR_PRES_Pos);
	}
}

/**
 * Initialize flash.
 */
void system_init_flash(uint32_t ul_clk)
{
	/* Set FWS for embedded Flash access according to operating frequency */
	if (ul_clk < CHIP_FREQ_FWS_0) {
		EFC->EEFC_FMR = EEFC_FMR_FWS(0) | EEFC_FMR_CLOE;
	} else {
		if (ul_clk < CHIP_FREQ_FWS_1) {
			EFC->EEFC_FMR = EEFC_FMR_FWS(1) | EEFC_FMR_CLOE;
		} else {
			if (ul_clk < CHIP_FREQ_FWS_2) {
				EFC->EEFC_FMR = EEFC_FMR_FWS(2) | EEFC_FMR_CLOE;
			} else {
				if (ul_clk < CHIP_FREQ_FWS_3) {
					EFC->EEFC_FMR = EEFC_FMR_FWS(3) | EEFC_FMR_CLOE;
				} else {
					if (ul_clk < CHIP_FREQ_FWS_4) {
						EFC->EEFC_FMR = EEFC_FMR_FWS(4) | EEFC_FMR_CLOE;
					} else {
						if (ul_clk < CHIP_FREQ_FWS_5) {
							EFC->EEFC_FMR = EEFC_FMR_FWS(5) | EEFC_FMR_CLOE;
						} else {
							if (ul_clk < CHIP_FREQ_FWS_6) {
								EFC->EEFC_FMR = EEFC_FMR_FWS(6) | EEFC_FMR_CLOE;
							} else {
								if (ul_clk < CHIP_FREQ_FWS_7) {
									EFC->EEFC_FMR = EEFC_FMR_FWS(7) | EEFC_FMR_CLOE;
								} else {
									EFC->EEFC_FMR = EEFC_FMR_FWS(8) | EEFC_FMR_CLOE;
								}
							}
						}
					}
				}
			}
		}
	}
}

/* @cond 0 */
/**INDENT-OFF**/
#ifdef __cplusplus
}
#endif
/**INDENT-ON**/
/* @endcond */
